Ever wish you could find out whether someone actually opened that email you sent, or whether they just ignored and trashed it? A service called Bananatag can tell you—but if you find that a little creepy, we've got the lowdown on how to protect yourself too.

How Bananatag Works

Think of Bananatag like iMessage or BBM for your email: when you send someone a message, you can track it to see if and when they read it, and if they click the links you put inside. It's actually nothing new: email marketers have been using the same tracking techniques for a long time, to tell how many people open their newsletters, click the links inside, and so on.

So how does it work? Bananatag embeds a small, 1 pixel by 1 pixel transparent image in each email, hosted on their servers. When you open the email, Bananatag knows that unique image has been accessed, and can then tell the sender their email has been opened. Similarly, it turns links into short links that head back to its server so they know when they're accessed (but keeping the original text of the link intact).

Bananatag is available as a Chrome or Firefox extension for Gmail, a plugin for Outlook, or use it with any other web client using a simple tweak to your contact's addresses. It's free for 5 messages a day, but $5 a month gives you unlimited tracking.

How to Avoid Being Tracked

Using a service like Bananatag could be useful for a number of reasons, but it's also creepy to think that your friends could be tracking the emails they send you this very same way. Luckily, there's an easy way around it: if you get an email that asks you to display images, just reject your mail client's request to display them. Obviously you can't do this for every email (since some will have pictures you want to open), but if you get an email that makes no mention of images but asks you to display them, that's a hint that the sender may be using a service like Bananatag.

More importantly, don't ever click a link in an email if you don't know where it goes. Hover over the link and check its destination in the bottom left corner of your window first. If the link text doesn't match the link that shows up in the bottom corner, that link is going somewhere else. Bananatag isn't out to get you; they just want to track your clicks, but other evildoers can use this same trick to get into your bank account, PayPal account, or something similar, so it's a good rule to follow. If the link text goes somewhere you trust, copy and paste it into your browser's address bar instead of clicking on it.

Bananatag is an interesting service with some worthwhile uses, but we could understand why one might find it creepy, too, so the techniques it uses are good to be aware of. You can't protect yourself fully (unless you never open images in emails), but it's good to be on the lookout should a service like this become more popular with, say, increasingly nosy friends. Hit the link to see more about the service.